Gaseous discharge device



June 7, 1932.

L. 'J'. BUTTOLPH GASEOUS DISCHARGE DEVICE Filed May 1, 192

2 Sheets-Sheet 1 Jun' 7,1932. BU TOLPH 1,861,620,

GASEOUS DISCHARGE DEVICE Filed May 1, 1926 2 Sheets-Sheet 2 THIN 7-'lLM OFMERCURY Patented June 7, 1932 UNITED STATES PATENT OFFICE LEROY J. BUT-TOLPH, OF GRANT'WOOD, NEW JERSEY, ASSIGNOR TO GENERAL ELECTRIC VAPOR LAMP COMPANY, OF HOBOKEN, NEW JERSEY, A CORPORATION OF NEW JERSEY GASEOUS DISCHARGE DEVICE Application filed May 1,

My present invention relates to electric vapor discharge devices which are energized by high frequency alternating, oscillating or interrupted currents and which are adapted for use as light sources and for use in the arts generally. The invention relates more.

particularly to devices having a gas or va- For example, in the induction lamp pro- I posed by Hewitt, wherein only an infinitesimal amount of vaporizable material is utilized, the operating coil is unable to start the lamp into operation,'smce it is impossible to produce enough heat energy from the coil in the microscopic film formed by the vaporizable substance to raise the vapor pressure to the starting point due to the fact that the condensing action of the bulb is in excess of the heating effect obtainable with the operating coil and a film of this type. I have overcome this difliculty of starting by providing the lamp bulb with a closed ring of mercury,

for instance, to cooperate with the o crating coil and of such dimensions and position as to intercept requisite amounts of the magnetic field thereby increasing its ability to absorb I energy and hence its power to evaporate mercury in excess of the condensing effect of the sphere, resulting in the rapid raising of the vapor pressure to the starting point and insuring rapid and certain starting of the lamp tube at, all times.

It is an object of this invention to provide a high frequencyinduction'vapor discharge device which is adapted under normal starting conditions to present or possess means which will sustain the flow of induced hi h frequency currents and which will provi e, store or contain or possess a vapor which will sustain in the field of a high frequency tap-rent discharge with-luminous and other el'ects.

1926. Serial No 105,951.

It is another object of this invention to provide a high frequency induction vapor discharge device which is adapted under normal starting conditions to present or possess a closed path comprising electrically conductive which is vaporizable.

It is another object of my invention to provide a high frequency induction vapor discharge device which is adapted under normal starting conditions to present or possess a closed path comprising electrically conductive material and which will provide vapor, and in which device the closed path may be discontinued or will discontinue after desired operating conditions have been instituted in the device.

Another object of the invention is to provide such a device in which the closed conductive path may be opened by the movement of the said vaporizable material.

A further object of this invention is to provide sucha device in which the closed path may be opened by the vaporization of said vaporizable material.

Other objects of this invention will appear from the drawings, the specification and the claims.

I In the drawings forming a part of this ap-,

\ plication:

a conducting coil connected .to a source of high frequency electric currentcin the field of which coil is a closed envelope having a body of vaporizable conducting material such as mercury therein, said envelope having a projection on the. interior wall thereof about which said vaporizable material extends in a closed electrical path.

' Fig. 2 is a plan view in section taken along the line 2'-2 of the envelope of Fig. 1.

Fig. 3 is an elevation view of an envelopesimilar to that of Fig. 1 mounted for tilting:

to cause the vaporizable material in the liq-1 uid form to flow from the ring forming proj'ection whereby the closed path is opened.

Fig. 4 is an elevation view of the device of Fig; 3'in the tilting position showing a liquid vaporizable material as having flowed from its ring forming position about the internal projection and also showing an electromagnetof vaporizable material with a spiral of open ended insulating tubing immersed therein.

- direction of, the arrows.

Fig. 8 is a vertical elevation view of the device of Fig. 7 in part section.

Fig. 9 is a horizontal section view taken along the line 9-9 of Fig. 7 looking in th Fig. 10 is an elevation view of a device comprising an envelope having a quantity of vaporizable material. therein and a thermostat positioned over the material which thermostat is in the form of a broken ring with its ends touching and which is adapted to have a high frequency current induced therein and adapted to'expand to draw the said ends apart as shown in dotted lines, and

Figs. 11 and 12' show in elevation view and in sectional plan view an envelope having a vaporizable material therein which with an exterior conductor having its ends sealed into the envelope forms a closed circuit suitable for supporting an induced high frequency current. A switch is provided in the outside conductor.

Fig. 13 shows an envelope having a flat bottom over which a quantity of vaporizable material such as mercury is spread to make a thin film. I

In Fig. 1 the inductance coil 1 is connected to the secondary 2 of the transformer 3, the spark gap 5 and the condenser 6 being connected in parallel and in series respectively with said coil 1 to produce a high frequency oscillatory current flow through said-fcoil- 1. In the magnetic field of said coil 1 is mounted the sealed envelope 8 whiclrcontains a quantit of mercury, or sodium, or potassium or an amalgam of these. or other materials which is in the form of a ring, the inward projection 12 being provided at the bottom of the envelope to form said material 10 into a closed ring.

In Figs. 3 and 4 the envelope8 has mounted thereabout the supporting frame-15 which is 4 provided with lug 16 pivoted to su port- 17 whereby the envelope may be tilte as into the position of Fig. 4 for the purpose of breaking the closed path which the materiallO forms in the normal position of the envelope. In Fig. 4 there is also shown as means for tilting the device an armature 18 fixed to the frame 15 near the pivot 16. In operable relation to the armature 18 is an electromagnet the discharge is starte 20 energized from the same source as said coil 3 and having a switch 21 in the circuit thereof for energizing and deenergizing it.

In the use and operation of the device of Figs. 1 and 2, with mercury used for the closed path 10, upon passage of high fre' quencycurrent through coil 1 current flow .is induced in'said closed path which heats it the vapor by the induced high frequency voltage and for thesubsequent conduction of current as'induced by said coil 1. This high frequency current which is induced to flow in the mercury vapor when that is ionized continues to flow by virtue of the fact that the vapor is further ionized by said flow and is in this manner. brought to a permanent current flow supporting 'condition. The ring or closed path 10 of mercury may be discontinued or retained. .It may be discontinued by the complete vaporization thereof in which case mercury is provided in the envelope in an amount that will completely vaporize under operating conditions of the devices. I 1

The ring or closed path 10 of mercury may also be disrupted-by tilting the envelope 8 to cause the mercury, or other conductor in the liquid state, to flow from about said pro- .jection 12 to break the ring. (See Figs. 3

and 4.) may be done before and for the purpose of starting the dischi trge by striking'an are at the ends of the mercury ring as it is being This breaking broken. The ring may" also be broken after the discharge is started and kept open to'prevent absorption of energy by the ring. This breaking of the ring may be done whether or not the mercury or other substance completely vaporizes.

In the form of my invention in which the ring 10 is .discontinued by vaporization thereof the ring may be of any suitable material such as a solid metal or alloy or an amalgam or in the liquid state-as is'mercury. Some materials suitable for this purpose are low melting metals such as lead, tin, bismuth, arsenic and so on or alloys of these and/or other metals, tellurium, iodine or amalgam of any of these with mercury. For use in the tiltable envelope any material may be used which will when heated supply a current supporting vapor and which is completely vaporizable to disrupt the ring, or which will be melted whereby the closed path may be disrupted by the flow thereof when the envelope is sufiiciently tilted to cause the moltenmaterial to flow from about said proj action 12. For use in a tiltable form of the envelope there may be used mercury, tin, lead, bismuth or the like or allo s or amalgam of some of these. The enve ope 8 when the device is used as a source of illumination or as a source of other radiant energy may be of glass or of fused quartz.

Fig. 5 shows a heating coil outside the envelope and a ring 26 of mercury, sodium,

potassium, magnesium, or an amalgam inthe envelope which would be vaporized by the heat from coil 25. The vaporizable material may, however, be in the form of an ordinary pool. The coil 25 is supported by the pivoted arm 28 which allows the coil to be removed from beneath the vapor device. Energization of coil 25 may be provided from the mains 29, 30 to which may also be connected the said coil 3. A switch 32 in the circuit of coil 25 provides for the disconnection of thecoil 25 from the mains when desired.

In Fig. 6 is shown a sealed envelope 8 having positioned thereina mass of gas absorptive material 34. which is shown as being in the form of a ring. This material may be of one of three classes; one, a material which is a non-conductor both in a contact with the gas and when gas has been expelled therefromytwo, a material which is a conductor both when associated with a gas and also alone without the gas; and three, a material which is a non-conductor when not associated with gas, which is a conductor when-a gas is absorbed thereby. In either case when the deviceis not operating and the discharge sustaining gas or vapor is absorbed in or absorbed by the material 34 and the device is energized as, for exam le, by means of the high frequency coil 1 of ig. 1, current is induced in the material 34 and heat produced by the resistance of the material which causes the "as contained thereby to be expelled and brought to a condition in which it will support an electric discharge induced by current passing through said coil 1. It is to be understood that the material 34 in-. stead of being in the form of a ring may be used as a solid lum when the characteristics of the device and o the energized circuit are such that acurrent of highenough value may be induced in the lamp to cause the as to be expelled and brought to current ischarge sustaining condition;

In Figs. 7, 8 and 9 the envelope 8 contains therein a body of material 36 which maybe mercury or' sodium or potassium or magnesium or alloys of any of these and any other suitable material from which a discharge supporting gas or vapor may be evolved. In the material 36 there is provided an 0 en ended tube 37 of insulating material whic serves to form the material 36 into one or more spiral turns to provlde a conductive'resistor having a closed path in which current may be induced by current flowing in coil 1 whereby the material 36 may be heated to evolve a vapor therefrom which will su ort a hi h frequenc electric discharge w ich may e induced y' said coil 1. When said tube or channel 37 is of a material lighter than the terial '43. This heat may material 36 it is of course necessary to pro-' vide means not shown) for holding the tube with a suificient part of it belowthe surface of the material 36 to provide the closed circuit. It can be seen, of course, that with the walls for separating the spiral conductorv from the main body of the material 36.

In Fig. 10 the envelope 8 has mounted.

therein by means of the supporting arm 40 the conducting ring or loo 42 which is of thermostatic material an which has a break therein to provide ends which at lower temperature are in contact with each other but.

which at raised temperatures move apart'and separate into the positions indicated by the dotted lines. This loop 42' is mounted above the body 43 of mercury, sodium or the like or of one of the materials represented by the number 34 in Fig. 6. Heat may be produced by current flow induced in 0011 42 and this heat may be utilized \for vaporizing the masupplemented material 43 itself. T e vapor is then ionized by heat produced thElough inductionin the and the device starte by arcing produced at the ends of coil 42 when that coil expands and draws the ends apart. I

In Figs. 11 and 12 the envelope 8 contains a body 46 of material such as mercury, sodium or a material the same as that used in the device of Fig. 6. Through the walls of the envelope 8 are sealed the ends of the conductor 48, which ends are under starting conditions in contact with said material 46. Said conductor48 may be provided with a switch 49 therein. As shown the material 46 and the conductor 48 through theswitch 49;

form a closed ath which can serve as asecondary to the igh frequency coil '1. It is to be understood, however, that conductor 48 may be formed into a plurality-of 100 s. and may also be of resistant material w ereby there is provided a heating coil which'may be energized through coil 1 to bring vapor in envelope 8 to discharge sustaining condition,

or to evolve a gas or vapor from said material 46 and 'alsoto bring the as tothe discharge sustaining condition. he vapor discharge'of course may be induced by high frequency current passing through. said coil 1 or some other suitable coil. It is to be furthcr understood that the ends of conductor 48 may be positioned above the surface of the material 46 where a spark produced therebetween may serve to ionize gas or .yapor.

evolved from said material 46 which may be heated by a rcsistorformed from said conductor 48.

- In Fig. 13 the envelope 8 contains a body of -mercury orother vaporizable material which is spread in a thin film across the bot- .tom of the envelope by reason of the flat section thereof. When the device is placed within the field of coil 1 currents are set up in the mercury, tendingto heat and vaporize it in the manner "discussed in connection with the previous figures, a discharge then taking place in the vapor under the influence of the ma netic field induced by coil 1.

t is of course understood that in the use of any of the devices above described current is induced in a gas or vapor therein by means of a high frequency current -whose field is in inductive relation to the device. It is to be further understood that the means for producing and supporting the inducing current may be used also for inducing a heating current in any of the various devices or a separate source of current or means for supporting the inducing current may be used.

In the starting and operation of any of these devices vapor is evolved from the carrier in the envelope and simultaneously with the production of the vapor or after a necessary amount of vapor is evolved a vapor discharge is started either by the direct action of a high frequency field or by some ionizing effect such as sparking in the devices of Fi s. 1, 3,7, 10 and 11 or by heating in any of t e devices illustrated and described. After the discharge has been started it is continued by a suitable high frequency field in the manners above described.-

path.

I claim:

' 1. In an inductive vapor discharge device, a closed path comprising a vaporizable electrically conductive liquid, said liquid-being present in such amount that under normal operating condltlons there Wlll have become evaporated an'amount thereof sufficient to open said path.

2. In an inductive vapor discharge device,

a sealed envelope, a closed electric path therein comprising a vaporizable electrically conductive liquid, said liquid being present in such amount that under normal operating V conditions there will have become evaporated an amount thereof suflicient to open said rent in said path to start the vapor discharge, and utilizing current generated in the path to vaporize the liquid thereof in sufficient amount to open, the circuit of said path.

5. In an inductive vapor discharge device having a continuous electrically conducting path comprising a vaporizable conducting liquid the method which comprises inducing a current in said path to start the vapor discharge and then removing sufiicient liquid from said path to disrupt it. a A

6. A vapor discharge device consisting of a sealed envelope having therein a closed path of vaporizable electrically conductive material, in combination with means for inductively opening said path.

7. A vapor discharge device consisting of a sealed envelope having therein a closed path of vaporizable electrically conductive material, in combination with means for opening said path responsive to current flow in said material.

8. A vapor discharge device consisting of a sealed envelope having therein a closed path of vaporizable electrically conductive material, in combination with means operative upon induced current flow through said closed path for opening it.

9. A vapor discharge device consisting of a sealed envelope having therein a closed path of vaporizable electrically conductive material, in combination with means opera-' tive upon induced current flow through said closed path foropening it and for drawing an arc whereby the device is set in operation.

10. The method of starting into operation a vapor are electric device having a vaporiza ble conductor in a closed electric circuit which comprises inducing current flow in said path to produce heat and thereby vaporize sufficient of the said vaporizable conductor to open said path and to produce a discharge sustaining vapor, and continuing induced current flow in said discharge sustaining vapor.

11. In combination, charge device, and means to produce an electromagnetic field of varying intensity in said device, said device cOmprising a sealed envelope having a vaporizable electrically conductive fluid therein, and means to deform said liquid from its normal globular shape to increase the linkage thereof with said field.

12. In combination, a gaseous electric discharge device, and means to produce an electromagnetic field comprising a sealed envelope having a vaporizable electrically conductive fluid therein, said fluid constituting a closed coil having a definite configuration.

charge device and means to produce an electromagnetic field of varying intensity in said device, said device comprising asealed envelope having a vaporizable electrically conductive fluidtherein, said fluid constituting a a gaseous electric dis- 13. In combination, a gaseous electric dis-- short circuited coil having a plurality of series turns in a plane normal to said field.

14. In combination, an inductive vapor discharge device, and means to produce an electromagnetic field of varying intensity in said device, said devlce comprising a container, a

vaporizable electrically conductive material in said container, and an inward projection in said container about which said material extends to form a closed electric path.

15. -In combination, an inductive vapor discharge device, and means to produce an electromagnetic field of varying intensity in said device, said device comprising a container, a vaporizable electrically conductive material in said container, and an inward projection in said container about which said material will collect upon cooling from the vaporized state to form a closed electric path about said projection.

16. In combination, an inductive vapor discharge device, and means to produce an electromagnetic field of varyinguntensity in said device, said device comprising a container, a vaporizable electrically conductive material in said container, and means for collecting said material upon condensation from the vaporized state to form a closed coil having a de nite configuration.

17. The method of operating an electric gaseous. discharge device which comprises creating a high frequencyjinductive field in said device, 'opening an electric circuit. in said device which is carrying current induced by said. field, and availing of the spark produced at rupture of said circuit to. lonize the gaseous atmos here in said device to initiate the desired in uctive'discharge therein.

18..The method of operatin an electric gaseous discharge device whic contains a uid conductor in the form of a ring which comprises creating a high frequency'field in said device to cause a current to flow in said ring, tilting said device to open said ring, and availing of the spark resultin from rupture of the circuit formed by sai ring to ionize the gaseous atmosphere in said device to initiate the desired inductive dischar'ge therein.

Signed at Hoboken, in the county of Hudson and State of New Jersey, this 28th day of April, A. D. 1926. v

LEROY J. BUTTOLPH. 

